BEIRUT — A car bomb ripped through a Shiite neighborhood in south Beirut on Tuesday, killing four people and sending plumes of smoke over the area in the latest attack to target supporters of Lebanon's militant Hezbollah group.

It was the second bombing in the neighborhood of Haret Hreik this month amid a series of attacks that have shaken Lebanon in a spillover of Syria's civil war into its smaller neighbor. The violence has targeted both Sunnis and Shiites, and further stoked sectarian tensions that are already running high as each Lebanese community lines up with its brethren on opposing sides of the Syrian conflict.

Tuesday's explosion shattered shop windows and set cars ablaze on a crowded commercial street. Footage broadcast by the Hezbollah-owned al-Manar television station showed medics hauling a man on a stretcher out of the area as flames engulfed a building. Debris littered the pavement.

The Lebanese Red Cross, in a statement to the state-run National News Agency, said that along with the four killed, 35 people were wounded in the explosion.

A group known as the Nusra Front in Lebanon claimed responsibility for the attack, saying it was in retaliation for Hezbollah's military support of President Bashar Assad's forces in Syria. The claim, which could not be independently verified, was posted on the group's Twitter account. Its name suggested ties to the al-Qaida-linked Nusra Front in Syria, one of the most powerful rebel factions.